Investment Securities - Unrealized Gross Losses and Fair Values of Securities in a Continuous Loss Position (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) security shares	Dec. 31, 2022 USD ($) security shares	Dec. 31, 2016 shares
Securities in the available-for-sale portfolio in a continuous loss position
Number of individual securities in a continuous loss position | security	222	275
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses	$ (564,000)	$ (213,696,000)
12 Months or More Unrealized Losses	(302,818,000)	(184,820,000)
Total Unrealized Losses	(303,382,000)	(398,516,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value	63,667,000	2,023,259,000
12 Months or More Fair Value	2,170,608,000	1,056,595,000
Total Fair Value	$ 2,234,275,000	$ 3,079,854,000
Investment securities comprised of collateralized loan obligations rated AA or better and obligations issued by local state and political subdivisions rated AA or better	5.00%	5.00%
Allowance for credit losses for its available-for-sale debt securities	$ 0	$ 0
Allowance for credit losses for its held-to-maturity debt securities	0	$ 0
Class B restricted shares
Time in Continuous Loss, Fair Value
Net realized gain	$ 40,800,000
Shares held | shares	0	120,000
Cost basis		$ 0
Number of shares sold | shares	120,000
Class B restricted shares | Visa
Time in Continuous Loss, Fair Value
Number of shares sold | shares			274,000
U.S. Treasury and government agency debt securities
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(2,962,000)
12 Months or More Unrealized Losses	$ (666,000)	(9,365,000)
Total Unrealized Losses	(666,000)	(12,327,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		83,870,000
12 Months or More Fair Value	32,503,000	67,112,000
Total Fair Value	32,503,000	150,982,000
Government-sponsored enterprises debt securities
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(699,000)
12 Months or More Unrealized Losses	(408,000)
Total Unrealized Losses	(408,000)	(699,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		44,301,000
12 Months or More Fair Value	19,592,000
Total Fair Value	19,592,000	44,301,000
Residential - Government-sponsored enterprises
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(73,954,000)
12 Months or More Unrealized Losses	(112,124,000)	(83,309,000)
Total Unrealized Losses	(112,124,000)	(157,263,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		645,338,000
12 Months or More Fair Value	783,297,000	515,117,000
Total Fair Value	783,297,000	1,160,455,000
Residential - Government agency
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(7,069,000)
12 Months or More Unrealized Losses	(1,121,000)
Total Unrealized Losses	(1,121,000)	(7,069,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		59,723,000
12 Months or More Fair Value	10,182,000
Total Fair Value	10,182,000	59,723,000
Commercial - Government agency
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(15,852,000)
12 Months or More Unrealized Losses	(50,270,000)	(28,995,000)
Total Unrealized Losses	(50,270,000)	(44,847,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		108,842,000
12 Months or More Fair Value	218,674,000	129,011,000
Total Fair Value	218,674,000	237,853,000
Commercial - Government-sponsored enterprises
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(7,348,000)
12 Months or More Unrealized Losses	(7,028,000)	(3,691,000)
Total Unrealized Losses	(7,028,000)	(11,039,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		94,657,000
12 Months or More Fair Value	86,431,000	24,916,000
Total Fair Value	86,431,000	119,573,000
Commercial - Non -agency
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(493,000)
12 Months or More Unrealized Losses	(281,000)
Total Unrealized Losses	(281,000)	(493,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		21,471,000
12 Months or More Fair Value	21,683,000
Total Fair Value	21,683,000	21,471,000
Government agency
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(74,797,000)
12 Months or More Unrealized Losses	(67,568,000)	(10,405,000)
Total Unrealized Losses	(67,568,000)	(85,202,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		596,907,000
12 Months or More Fair Value	471,150,000	56,415,000
Total Fair Value	471,150,000	653,322,000
Government-sponsored enterprises
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses		(21,916,000)
12 Months or More Unrealized Losses	(61,856,000)	(49,055,000)
Total Unrealized Losses	(61,856,000)	(70,971,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value		198,108,000
12 Months or More Fair Value	363,970,000	264,024,000
Total Fair Value	363,970,000	462,132,000
Collateralized Loan Obligations
Time in Continuous Loss, Unrealized Losses
Less Than 12 Months Unrealized Losses	(564,000)	(8,606,000)
12 Months or More Unrealized Losses	(1,496,000)
Total Unrealized Losses	(2,060,000)	(8,606,000)
Time in Continuous Loss, Fair Value
Less Than 12 Months, Fair Value	63,667,000	170,042,000
12 Months or More Fair Value	163,126,000
Total Fair Value	$ 226,793,000	$ 170,042,000